Utilisation of Environmental Impact Assessment (EIA) Technique in assessment of impact of human interference on natural ecology of estuaries : a case study of Mersey estuary

Aliero, BL

Abstract

A Conceptual study of the impacts of human activities on the
natural ecology of estuaries was carried out. The Mersey Estuary
was used as a case study. Environmental Impact Assessment
Techniques (EIA) was used to identify and evaluate impacts
generated by various activities of Man on estuaries.
The study was conducted with materials and data gathered
from scientific papers, documents, reports and other related
literature sources.
The findings of the research reveal that estuaries exist in
several forms and shape. They are characterised by graded
salinity ranging from marine condition (3.5%) to fresh water
(0.05%) and periodic and spontaneous tidal movements. Estuaries
are highly productive ecosystems and support large wildlife and
fish.
For many years Man has exploited estuarine resources.
However, in the last two hundred years, the advent of the
industrial revolution led to dramatic growth of navigation and
establishment of industries close to estuarine waters.
Consequently estuaries attracted large human populations which
discharged sewage along with industrial effluent direct into
their waters causing rapid deterioration in water quality and
severe distress of the biota.
The Mersey Estuary is typical of such industrialized
estuaries. The level of engineering modification and the extent
of pollution witnessed in the Estuary is possibly unparalleled
by any other estuary in the U. K. These activities have
significantly affected the ecosystem of the Mersey and the socioeconomic
lif e of people living within its catchment boundary and
beyond.
EIA has become an important tool in environmental planning
and management. I have used its principles and techniques in the
identification and analysis of impacts caused by activities of
Man on the Mersey Estuary.
Analysis of results indicate that the construction of
training wall along the sea channels and the building of the
Manchester Ship Canal were most important, reducing estuarine
capacity and the stabilization of the inner estuary navigation
channel. The heavy organic load from sewage and industry
discharged directly into the estuary caused severe deficiency of
dissolved oxygen and consequent loss of fish and wildlife. The
drive to clean up the Estuary started in the 1970s and so far
positive changes are being recorded showing improved wildlife
which reflect general improvement in the whole Estuary.

Citation

Aliero, B. Utilisation of Environmental Impact Assessment (EIA) Technique in assessment of impact of human interference on natural ecology of estuaries : a case study of Mersey estuary. (Thesis). University of Salford

• Thesis Type: Thesis
• Deposit Date: Aug 5, 2011
• Publicly Available Date: Aug 5, 2011
• Award Date: Jan 1, 1994